Olefins (e.g., ethylene, propylene, butenes, butadiene) and BTX (benzene, toluene, and xylenes) are basic and essential intermediates of the petrochemical industry. They are mainly produced through thermal cracking (or steam pyrolysis) of petroleum gases and distillates such as naphtha, kerosene or even gas oil. To obtain high yields of olefin and BTX, the preferred feeds for the steam cracker should be highly paraffinic with low aromatic content, because these feedstock properties help reduce undesired products and coke formation.
By upgrading crude oils in a hydroprocessing reactor, the linear paraffinic properties are improved and may be fed directly to a steam cracker, thereby enabling a larger amount of olefins and aromatics to be produced from crude oil directly.